The wrist is the joint formed at the intersection of the radius, the ulna, the carpals and the metacarpals. The wrist is the most frequently injured area of the upper extremity with three fourths of wrist injuries involving a fracture of the distal radius, and/or of the radius. These injuries usually present in an emergency room setting, and often involve a fall on an outstretched hand. While the past conventional wisdom has included a belief that such injuries will tend to heal sufficiently on their own, there is often a loss of function and an early onset of arthritis that can be precipitated by the misdiagnosis and improper treatment of such injuries.
The treatments known for wrist trauma have included external stabilization and fixation such as by plaster casts, external fixators, and orthopedic plates. Casting alone, presents the possibility of misalignment of the fragments which can lead to severe loss of function and early onset of arthritis, if the fracture is not properly reduced, and/or if the fragments do not stay in a reduced state, in particular where the patient is not compliant. External fixators have been demonstrated to have an efficacy, but are cumbersome, cosmetically unappealing, and can lead to the possibility of infection at the attachment sites.
Accordingly, surgeons often consider methods of internal fixation, which typically include wire and/or screws, and plates. One issue with wires is that a construct is time-consuming to construct; and screws alone, often do not provide the stability required for fusion of the fragments. Plates have the benefit of providing a construct that is designed for ease of implantation, and at the same time have the disadvantage that there is a significant variety in the shape and size of individual bones. Further, in particular, the radius bone is relatively small so that individual variations are relatively more significant than in larger bones, such as the femur, the pelvis, and the humorous. Moreover, the flesh surrounding the radius on the underarm or volar (thumb) side is particularly dense with tendons, ligaments, nerves and blood vessels all of which are less forgiving of the intrusion of a metal construct than muscle or fatty tissue.